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3 years ago

Which of the following is true of machines?

1 answer:

6 0

The right answer for the question that is being asked and shown above is that: "A. Machines increase the amount of force required to do a task. " The statement that is true about machines is that A. Machines increase the amount of force required to do a task.

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Match each literary device with the excerpt in which it is used.

kirill [66]

Answer:

euphemism oxymoron dramatic irony Excerpts Literary Devices In this story I read, Karen assumes her sister Mira is flushed with joy at learning of her eldest son's imminent return from the battle front. But the narrator makes it clear that Mira is beginning to wonder about the anti-war letters she recently sent to the president. "Marla, don't tease Sandy about how much she's been eating lately. For all you know she might have another bun in the oven." Unsure if he was really safe from the tiger he spotted earlier, Johan's heart beat quickly as he crouched and listened to the screaming silence of the forest. I rights reserved

3 0

3 years ago

Read 2 more answers

During a compaction test in the lab a cylindrical mold with a diameter of 4in and a height of 4.58in was filled. The compacted s

Ray Of Light [21]

Answer:

part a : The dry unit weight is 0.0616  $lb/in^3$ 

part b : The void ratio is 0.77

part c : Degree of Saturation is 0.43

part d : Additional water (in lb) needed to achieve 100% saturation in the soil sample is 0.72 lb

Explanation:

Part a

Dry Unit Weight

The dry unit weight is given as

$\gamma_{d}=\frac{\gamma}{1+\frac{w}{100}}$

Here

$\gamma_d$ is the dry unit weight which is to be calculated
γ is the bulk unit weight given as

$\gamma =weight/Volume \\\gamma= 4 lb / \pi r^2 h\\\gamma= 4 lb / \pi (4/2)^2 \times 4.58\\\gamma= 4 lb / 57.55\\\gamma= 0.069 lb/in^3$

w is the moisture content in percentage, given as 12%

Substituting values

$\gamma_{d}=\frac{\gamma}{1+\frac{w}{100}}\\\gamma_{d}=\frac{0.069}{1+\frac{12}{100}} \\\gamma_{d}=\frac{0.069}{1.12}\\\gamma_{d}=0.0616 lb/in^3$

The dry unit weight is 0.0616  $lb/in^3$ 

Part b

Void Ratio

The void ratio is given as

$e=\frac{G_s \gamma_w}{\gamma_d} -1$

Here

e is the void ratio which is to be calculated

$\gamma_d$ is the dry unit weight which is calculated in part a
$\gamma_w$ is the water unit weight which is 62.4 $lb/ft^3$ or 0.04 $lb/in^3$

G is the specific gravity which is given as 2.72

Substituting values

$e=\frac{G_s \gamma_w}{\gamma_d} -1\\e=\frac{2.72 \times 0.04}{0.0616} -1\\e=1.766 -1\\e=0.766$

The void ratio is 0.77

Part c

Degree of Saturation

Degree of Saturation is given as

$S=\frac{G w}{e}$

Here

e is the void ratio which is calculated in part b

G is the specific gravity which is given as 2.72

w is the moisture content in percentage, given as 12% or 0.12 in fraction

Substituting values

$S=\frac{G w}{e}\\S=\frac{2.72 \times .12}{0.766}\\S=0.4261$

Degree of Saturation is 0.43

Part d

Additional Water needed

For this firstly the zero air unit weight with 100% Saturation is calculated and the value is further manipulated accordingly. Zero air unit weight is given as

$\gamma_{zav}=\frac{\gamma_w}{w+\frac{1}{G}}$

Here

$\gamma_{zav}$ is the zero air unit weight which is to be calculated

$\gamma_w$ is the water unit weight which is 62.4 $lb/ft^3$ or 0.04 $lb/in^3$

G is the specific gravity which is given as 2.72

w is the moisture content in percentage, given as 12% or 0.12 in fraction

$\gamma_{zav}=\frac{\gamma_w}{w+\frac{1}{G}}\\\gamma_{zav}=\frac{0.04}{0.12+\frac{1}{2.72}}\\\gamma_{zav}=\frac{0.04}{0.4876}\\\gamma_{zav}=0.08202 lb/in^3\\$

Now as the volume is known, the the overall weight is given as

$weight=\gamma_{zav} \times V\\weight=0.08202 \times 57.55\\weight=4.72 lb$

As weight of initial bulk is already given as 4 lb so additional water required is 0.72 lb.

4 0

3 years ago

Zinc metal (Zn) and sulfur powder (s) undergo a chemical reaction to form zinc sulfide (ZnS) which equation represents this chem

dexar [7]

Zinc metal (Zn) reacts with sulfur (S) to create zinc sulfide (ZnS), and the chemical reaction is: Zn (s) + S (s) = ZnS (s).

Importance of Zinc (Zn) and sulfur (S):

Zinc(Zn) is a vital element that our systems need to absorb food and nutrients as well as create healthy skin and bones. Zinc(Zn) ions play a crucial role in a number of the body's enzymes.
Sulfur(S) is a pale yellow, tasteless, brittle solid that is also necessary for life. It is found in many proteins as well as the amino acids cysteine and methionine. It is a trace element found in bone minerals, bodily fluids, and lipids.

Chemical reaction -

In this experiment, heating a zinc(Zn) and sulfur(S) combination causes an interesting chemical reaction. A blinding flash of light, hot sparks, a hissing sound, and a cloud of white smoke in the shape of a mushroom are produced.

Therefore, the following chemical processes are taking place in the reaction: Zn (s) + S (s) = ZnS (s).

Learn more about Zinc(Zn) here:

brainly.com/question/13890062

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8 0

2 years ago

Ques

Amanda [17]

Answer:

When a particle or a system of particles move in a system where no external force acts, then the total linear momentum of the particle system remains constant.

Explanation:

Given data:

Total mass of the skateboarder, $m_{1} = 70 \ kg$